From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
A call to tracefs_kprobe_clear() will attempt to disable all kprobes. If
any kprobe is set, and the @force parameter is set, it will fail with
errno set to EBUSY. If @force is set, then it will attempt to disable all
the defined kprobe events and then clear it.
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
include/tracefs.h | 2 +-
src/tracefs-kprobes.c | 136 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 137 insertions(+), 1 deletion(-)
diff --git a/include/tracefs.h b/include/tracefs.h
index 47b05b3f55e7..54c461e85a2b 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -212,5 +212,5 @@ void tracefs_trace_pipe_stop(struct tracefs_instance *instance);
int tracefs_kprobe_raw(const char *system, const char *event,
const char *addr, const char *format);
-
+int tracefs_kprobe_clear(bool force);
#endif /* _TRACE_FS_H */
diff --git a/src/tracefs-kprobes.c b/src/tracefs-kprobes.c
index e4b28cff9f08..48a4f090f041 100644
--- a/src/tracefs-kprobes.c
+++ b/src/tracefs-kprobes.c
@@ -68,3 +68,139 @@ int tracefs_kprobe_raw(const char *system, const char *event,
return ret < 0 ? ret : 0;
}
+
+struct instance_list {
+ struct instance_list *next;
+ struct tracefs_instance *instance;
+};
+
+static int disable_events(const char *system, const char *event,
+ struct instance_list *list)
+{
+ int ret;
+
+ ret = tracefs_event_disable(NULL, system, event);
+ if (ret < 0)
+ return ret;
+
+ while (list) {
+ ret = tracefs_event_disable(list->instance, system, event);
+ if (ret < 0)
+ return ret;
+ list = list->next;
+ }
+
+ return 0;
+}
+
+static int build_instances(const char *name, void *data)
+{
+ struct instance_list ***ptr_next = (struct instance_list ***)data;
+ struct instance_list **next = *ptr_next;
+ struct tracefs_instance *instance;
+ struct instance_list *list;
+
+ instance = tracefs_instance_alloc(NULL, name);
+ if (!instance)
+ return -1;
+
+ list = malloc(sizeof(*list));
+ if (!list) {
+ tracefs_instance_free(instance);
+ return -1;
+ }
+
+ list->instance = instance;
+ list->next = *next;
+ *next = list;
+ *ptr_next = &list->next;
+ return 0;
+}
+
+static void free_instance_list(struct instance_list *list)
+{
+ struct instance_list *n;
+
+ while (list) {
+ n = list->next;
+ tracefs_instance_free(list->instance);
+ free(list);
+ list = n;
+ }
+}
+
+/**
+ * tracefs_kprobe_clear - clear kprobe events
+ * @force: Will attempt to disable all kprobe events and clear them
+ *
+ * Will remove all defined kprobe events. If any of them are enabled,
+ * and @force is not set, then it will error with -1 and errno to be
+ * EBUSY. If @force is set, then it will attempt to disable all the kprobe
+ * events in all instances, and try again.
+ *
+ * Returns zero on success, -1 otherwise.
+ */
+int tracefs_kprobe_clear(bool force)
+{
+ struct instance_list *list = NULL;
+ struct instance_list **plist = &list;
+ char *content;
+ char *saveptr;
+ char *system;
+ char *event;
+ char *p;
+ int ret;
+
+ ret = tracefs_instance_file_clear(NULL, KPROBE_EVENTS);
+ if (!ret)
+ return 0;
+
+ if (!force)
+ return -1;
+
+ /* Attempt to disable all kprobe events */
+ content = tracefs_instance_file_read(NULL, KPROBE_EVENTS, NULL);
+ if (!content)
+ return -1;
+
+ ret = tracefs_instances_walk(build_instances, &plist);
+ if (ret < 0)
+ goto out;
+
+ ret = -1;
+ p = strtok_r(content, ":", &saveptr);
+ if (!p)
+ goto out;
+
+ for (;;) {
+ p = strtok_r(NULL, "/", &saveptr);
+ if (!p)
+ goto out;
+
+ system = p;
+
+ p = strtok_r(NULL," ", &saveptr);
+ if (!p)
+ goto out;
+ event = p;
+
+ if (disable_events(system, event, list) < 0)
+ goto out;
+
+ ret = tracefs_instance_file_clear(NULL, KPROBE_EVENTS);
+ /* On success stop the loop */
+ if (!ret)
+ goto out;
+
+ ret = -1;
+ p = strtok_r(NULL, "\n", &saveptr);
+ if (!p)
+ goto out;
+
+ p = strtok_r(NULL, ":", &saveptr);
+ }
+ out:
+ free(content);
+ free_instance_list(list);
+ return ret;
+}
--
2.30.2
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